Instructions

Preheat the oven to 350F. Grease and flour two 8-inch cake pans.

First prepare the cake. In a large bowl, sift together the flour, sugar, baking soda, and cocoa. Gradually add the mayonnaise, water and vanilla and blend in. Turn the mixture into the prepared cake pans and bake for 30 minutes.

Meanwhile, make the frosting. In a saucepan, combine the milk and the flour to make a paste. Heat, stirring constantly, until thickened. It will have the consistency of library paste. Cool.

In a bowl, cream the butter and sugar. Add the cooled flour and milk mixture and the vanilla. Blend in. Add the chocolate and beat until firm but fluffy.